Optical radiation can be used to view and to characterize tissues within a patient's body. Visible light may be useful, for example, for imaging and for acquiring spectroscopic information about a body lumen. Non-visible wavelengths may be useful as well. For example, intracorporeal devices sensitive to infrared radiation may be used to provide temperature information in order to identify diseased portions of a vessel wall. Such imaging devices typically use an optical fiber to carry light of visible and non-visible wavelengths.
Optical fibers convey optical radiation, and may be used to carry optical radiation from a source to a sensor. Optical fibers, particularly single-mode optical fibers, may be of extremely small diameters, as small as a few thousandths of an inch, making them suitable for introduction into small body lumens. Conveyance of optical radiation into and out of a body lumen is useful for imaging, spectroscopy, illumination, optical sensing, temperature sensing, photoactivation of drugs and compounds at an intraluminal location, photoablation, optical heating, and other applications. Optical instruments may use light of visible or of non-visible wavelengths. Visible light may be useful, for example, for imaging and for acquiring spectroscopic information about a body lumen.
For example, intracorporeal imaging is useful for diagnosing and treating many serious medical conditions such as, for example, arteriosclerosis. Intracorporeal optical imaging devices have been described, as in Brezinski et al., Circulation 93:1206-1213 (1996); Tearney et al., Optics Letters 21:543-545 (1996); Tearney et al., Science 276:2037-2039 (1997); Brezinski et al., J. Surgical Research 71:32-40 (1997); Brezinski et al., Heart 77:397-403 (1996); and Fujimoto et al., Annals N.Y. Acad. Sci. 838:95-107 (1998). Intracorporeal optical imaging devices have been described, as in U.S. Pat. Nos. 5,321,501 and 5,459,570 to Swanson et al., and U.S. Pat. No. 6,134,003 to Tearney et al. Non-visible wavelengths may be useful as well. For example, optical catheters sensitive to infrared radiation may be used to provide temperature information in order to identify diseased portions of a vessel wall, as disclosed in U.S. Pat. No. 5,935,075 to Cassells et al. All patents and patent applications, both supra and infra, are hereby incorporated by reference in their entirety.
Introduction and advancement of intracorporeal instruments through body lumens is typically aided by a guidewire, which is a thin, flexible device used to provide a guiding rail to a desired location within the vasculature (or other body cavity) of a patient. Following positioning of the guidewire, other larger or more fragile instruments may be guided to the desired location along the guidewire.
In angioplasty and other intraluminal procedures, guidewires are used to carry or guide devices such as a catheters to their desired locations. It is preferred that guidewires be capable of loading and unloading different catheters or other devices, as different devices are often required or desired during a single clinical procedure. A guidewire that is used to carry, load or unload other intracorporeal instruments or devices is termed to be used in its therapeutic mode. Most guidewires are capable of being used only in therapeutic mode.
In addition to guiding and carrying other devices, guidewires may themselves be clinical instruments, as, e.g., when the guidewire is an optical guidewire (OGW) such as an optical imaging guidewire capable of receiving and transmitting optical radiation from within the body lumen for obtaining an image or an optical guidewire adapted to measure temperature or other physical characteristic within a body lumen.
A guidewire that is used as an optical instrument is used in “optical mode.” Reception of optical radiation from within a body lumen provides clinicians with information useful in many clinical situations and procedures. Intracorporeal optical imaging is useful for the placement of guidewires, catheters, endoscopes, and other instruments in desired locations within a patient's body, such as within a blood vessel during angioplasty or the colon during colonoscopy. Optical imaging or spectroscopy of an artery and artery wall can provide information about the type, severity and extent of an occlusion or lesion and so improve the diagnosis and treatment of the patient. Optical radiation may be used to heat or ablate tissue, or to activate or inhibit photosensitive compounds located within a body lumen. Thus receiving and emitting optical radiation by an intracorporeal instrument can be of great importance to the success of a clinical procedure.
Reception of or emission of optical radiation directed to more than a single particular region within body lumen often requires rotation and longitudinal translation of the imaging guidewire in order to obtain images from a variety of orientations and positions within a body lumen. In order to obtain, display or analyze optical radiation, a guidewire must often be connected with external equipment such as a light source and image acquisition instrumentation. In addition, optical instruments may be rotated to provide a full view of regions of interest. Thus, a secure mechanical connection is required in order to accurately and stably control the location of a guidewire in guiding mode and to insure that images are faithfully transmitted when an OGW is used in optical mode. Moreover, it is imperative that the sterility of the guidewire be maintained during clinical procedures. In addition, it is preferred that clinical procedures be as rapid and efficient as possible. It is often useful to capture an optical fiber with a rigid or durable sleeve to protect the fiber and to provide an effective mechanical connection between an optical fiber and other devices. Such a sleeve is termed a “ferrule.”
Accordingly, devices and methods for rotating an OGW and for effecting optical connections between an OGW and other equipment, including devices and methods for easily, securely and sterilely connecting and disconnecting an optical guidewire to non-sterile equipment are desired.